Adding to this: I am convinced that who has PSCS has a very good app. There are things that are made much easier, some inprovements for people with better-than-average digital cameras (RAW mode must also be supported on the camera), less gaps in histograms when tweaking levels due to 16 bit support, etc etc.
For me, personally, I see no immediate need to upgrade. I take a lot of pictures, but I don't own a digital camera as DC's don't yet answer my needs (most of all due to a lack of money to buy a single reflex digital with three separate lenses, and a wide angle lens that matches a 20mm on trad. camera's isn't available due to the smaller sensitive surface of the cam.).
I can do all I want with 7, there's still so much to discover, and, adding to this the fact that over here the upgrade is at least one third more expensive, I wait, and see what's left after the publicity hurricane has calmed down.
No more than that.
I hope to read reviews from our gang here at PSG because I know them. So Rick and the others: please, when you know CS better: let me know your personal thoughts and impressions that fall outside the Adobe brochure.